The present invention relates generally to footwear, and more particularly to footwear having recesses for accommodating protrusions of the foot and/or one or more pads for reducing swelling of the ankle.
As illustrated in FIGS. 1–3, typical human feet, designated by the reference character O, have protrusions resulting from skeletal structures beneath the skin. For example, a head H1 of a first metatarsal M1 and a base B1 of a first proximal phalanx P1 cause a protrusion at a base of a first toe T1 (i.e., the great toe) which extends from the foot in a medial direction X1 (i.e., toward a centerline of the body) as shown in FIG. 2. A head H5 of a fifth metatarsal M5 and a base B5 of a fifth proximal phalanx P5 cause a protrusion at a base of a fifth toe T5 which extends from the foot in a lateral direction X2 (i.e., away from the centerline of the body). Further, the fifth proximal phalanx P5 of the fifth toe T5 extends farther laterally than a fifth middle phalanx MP5 and a fifth distal phalanx DP5 so the proximal phalanx forms a protrusion on the fifth toe immediately in front of the protrusion caused by the head H5 of the fifth metatarsal M5 as shown in FIG. 2. Several protrusions are caused by metatarsal and mid-tarsal bones MT which protrude upward from the top of the foot O as shown in FIG. 1. Further, in the ankle area the tibia T has a protrusion called the medial malleolus MM that is located at the medial side of the distal head of the tibia. Similarly, the fibula F has a protrusion called the lateral malleolus LM that is located at the lateral side of the distal head of the fibula.
Typical footwear has an upper attached to a sole. The upper surrounds the foot O to retain it in position inside the footwear when walking or running. As the foot O moves inside the footwear, the upper exerts pressure on features of the foot including the previously described protrusions. The protrusions also move relative to the upper, causing friction between the upper and the skin covering the protrusions. Sometimes the pressure and friction cause ailments such as swelling and irritation of the skin and underlying tissue. Some conventional footwear has extra padding in some of the areas of the upper corresponding to the protrusions to alleviate these ailments. However, the padding wears out over time and becomes less effective in alleviating the ailments. Moreover, the extra padding in conventional footwear is not precisely anatomically positioned for alleviating the ailments.
Another problem associated with conventional footwear is that it does not conform to the structure of the foot because the upper, and the padding in particular, is not shaped like a foot. For example, many conventional shoes have scalloped collars for accommodating the ankle bones. The scallops of the collar are generally symmetric about a longitudinal centerline of the footwear. However, the ankle bones themselves are not symmetric about a longitudinal axis L of the foot. Rather, the tibial protrusion T is above and in front of the fibular protrusion F. As a result, the collar of the shoe does not conform to the protrusions, and the collar either rubs one of the protrusions or it does not support the ankle A. Because conventional footwear is not shaped to accommodate the ankle bones, the ailments discussed above are more likely to occur. The present invention takes into account the structure of the foot to reduce the likelihood of such ailments.
Yet another problem associated with conventional footwear is an ineffectiveness at reducing interstitial fluid build-up and swelling at the ankles A. Such fluid build-up and swelling is a common ailment associated with running, walking, and other physical activity and is caused, in part, by the inability of the lymphatic system to remove interstitial fluids that are produced naturally when tendons, ligaments, and other tissues surrounding the ankle are placed under stress. As a result, swelling occurs. This swelling can be aggravated by the footwear itself, which may constrict the efficient flow of bodily fluids toward the upper body and heart. In any event, a swollen ankle can inhibit movement and be painful. The present invention takes into account the structure of the ankle and the inability of the lymphatic system to remove interstitial fluids to reduce ankle swelling.